Stabilization of palm oils by using Ficus exasperata leaves in local processing methods.

Abstract

This work was done to ascertain the efficacy of the local use of Ficus exasperata leaves in processing palm oils to improve and stabilize the quality. Palm oils were obtained from the ripe fruits of Elaeis guineensis and Elaeis guineensis var virescens, including Ficus exasperata leaves in the traditional processing procedures--cooking and soaking the fruits in water. Phytochemical analysis of the Ficus leaves and the oils were performed. The quality of the oils were assessed in terms of saponification, acid and peroxide values, and free fatty acid content. Results showed the presence of phenolic compounds, terpenoids, alcohols and carbonyl compounds in the leaves. Oil from both oil palm varieties contained appreciable amounts of carotenoids, flavonoids and sterols, but only the Elaeis guineensis var virescens oil contained saponins. The use of the Ficus leaves eliminated saponins and the foaming tendencies of the var virescens oil, but reduced the sterol levels and increased the carotenoid levels in the oils from both oil palm varieties. Oils processed by soaking of fruits and use of the Ficus leaves had slightly greater saponification values, while oils processed by cooking of fruit and use of leaves had reduced FFA, acid and peroxide values. The use of Ficus exasperata leaves makes for a better stabilized oil with potentially good keeping qualities.